Auditorium-chair portable writing table

ABSTRACT

An auditorium-chair and portable-writing-table combination in which a portable writing table having a writing surface on its upper side, has downwardly-opening U-shaped channels on its underside that are received on the respective arm rests on each side of the seat, one channel being laterally and angularly displaceable with respect to the board to accommodate variations in the spacing and the angular relationship of a pair of arm rests. The other channel is fixed against lateral and angular displacement to render the mounted table stable against lateral displacement. The laterally displaceable channel is formed with transverse slots in its bite portion that loosely receive the headed studs secured to the table.

INTRODUCTION

[0001] 1. Field of the Invention

[0002] This invention relates to portable writing tables for students seated in auditorium chairs having arms, and more particularly to a portable writing table that is readily mounted on an auditorium-chair's arms over a range of arm spacings and arm variations from parallelism, and firmly held against lateral shifting and vertical displacement and restrictively against endwise shifting.

[0003] 2. Background of the Invention

[0004] In auditoriums or lecture halls, the chairs usually have pivoted seats mounted via side supports secured to the auditorium floor; the side supports including an arm rest so that one obtains on each side of the seated student's body. Existing portable writing tables provided for such chairs employ an overlarge rigid “U”-shaped plastic channel glued open-faced to the bottom of each side of the table. After a student is seated, he or she places her given writing table with its writing surface upwards and so that it straddles the front of his or her body, and then downwards so that the over-wide downwardly-opening “U”-shaped plastic channels on its underside are readily received on the arm rests at the sides of the seat. The sides off the bytes of the downwardly-opening “U”-shaped plastic channels must be widely spaced to accommodate a range in the spacing of a chair's arm rests and in their variations from parallelism. Unfortunately, this frequently does not result in a horizontally-stable waiting table as the tolerance built into the spacings of the sides of the U-shaped plastic channels allows them and the writing table to slide laterally upon the arm rests. Not only may some sidewise or lateral shifting of the writing table occur, but also endwise shifting as nothing restrains the movement in and out direction except the student's body and the friction resulting from the table' weight as supplemented by that of the student' arms and body. Moreover, such writing tables are also easily displaceable upwards, as upon the writer adjusting his or her legs.

[0005] 3. Prior Art

[0006] Prior Art includes the aforementioned portable writing table with the “U”-shaped plastic channel glued open-faced to the bottom of each lateral edge of the table.

SUMMARY OF THE INVENTION

[0007] Accordingly, it is an object of the invention to provide a more-stable-when-mounted portable auditorium-chair writing table.

[0008] A more particular object of the invention to provide a more-horizontally-stable-when-mounted portable auditorium-chair writing table.

[0009] A still more particular object of the invention to provide a laterally-stable-when-mounted portable auditorium-chair writing table.

[0010] Another still more particular object of the invention to provide a more-endwise-stable-when-mounted portable auditorium-chair writing table.

[0011] A further still more particular object of the invention to provide a vertically-stable-when-mounted portable auditorium-chair writing table.

[0012] A specific object of the invention to provide a portable auditorium-chair writing table that can accommodate a wide variation in arm rest spacings and parallelism and yet be laterally stable when mounted.

[0013] Another specific object of the invention to provide a portable auditorium-chair writing table that can accommodate a wide variation in arm rest spacings and parallelism and yet be vertically stable when mounted.

[0014] A further specific object of the invention to provide a portable auditorium-chair writing table that can accommodate a wide variation in arm rest spacings and parallelism and yet be resistant to endwise shifting when mounted.

[0015] A yet further specific object of the invention to provide a portable auditorium-chair writing table that accommodates a wide variation in arm rest spacings and parallelism and is resistant to endwise shifting when mounted, and that can be readily fixed in a convenient position endwise.

[0016] A specific object of the invention to provide a more-stable-when-mounted portable auditorium-chair writing table that is simple of construction and inexpensive of manufacture.

[0017] Another specific object of the invention to provide a more-stable-when-mounted portable auditorium-chair writing table that is easily mounted and dismounted and safe in use.

[0018] These and other objects of the invention are achieved partially by the replacement of one of the fixedly-mounted, widely-spaced-sides “U”-shaped channel, with a fixedly mounted “U”-shaped channel having more closely spaced sides and which snugly engage the sides of the chair arm rest to prevent lateral shifting of the writing table. The other one of the fixedly-mounted, widely-spaced-sides “U”-shaped channel is replaced with with an adjustably-mounted one. The adjustably mounted 37 U”-shaped channel can be moved laterally and rotationally with respect to the writing table to accommodate variation in the spacing and angularity of the chair arm rests with respect to each other.

[0019] Easy mounting and dismounting of the writing table are achieved by pivotally securing one leg of the channel to its bite and so that it is biased to a home position in which it engages the side of its arm rest and from which it can be moved to open the channel to facilitate mounting the channel on its arm rest and especially removing it therefrom. Pivoting the biased channel leg against its bias from the home position to remove the channel from the arm rest, is especially useful because the free end of the biased-channel leg is formed with an inwardly- and upwardly-extending portion which extends underneath the arm rest in the mounted condition of the table and latches the channel and hence the table against upward movement. Preferably this leg is the outside leg of the “U”-shaped channels.

[0020] The other or fixed leg of a “U”-shaped channel is formed on its free or lower end with an outwardly- (of the channel) and downwardly-flaring portion which serves to help steer the channel onto the corresponding chair arm during mounting or installing operations; the table normally being mounted by engaging the fixedly-mounted “U”-shaped channel on its chair arm first. The biased inwardly-extending portion of the pivoted leg not only helps steer the U-shaped channel onto the corresponding arm during mounting operations, but it yields outwardly if it hasn't been manually pivoted out of the way, to allow the channel to be received on the chair arm. An element associated with the byte portion of the channel positions the pivotally-secured channel leg in a home position wherein the channel can always be received on its chair arm.

[0021] A feature of the invention is that the inwardly-extending portion on the pivoted leg of the channel and the outwardly-flaring potion of the other or fixed leg of the channel both help to steer a channel onto its arm rest.

[0022] Variations in the spacing and from the parallelism of the chair's two arm rests impede mounting a writing table on the chair's arms rest. These variations from standard are accommodated by floatingly mounting the adjustable “U”-shaped channel on the underneath of the table. To this end, it is formed in its bite portion with a series of sidewise-extending slots which are received on headed studs fixed to the underside of the table as by a plate secured thereon. The slots allow sidewise shifting on the studs of the adjustable “U”-channel with respect to the table to accommodate different spacings of the chair arms from each other; the heads of the studs retaining the channel horizontally in place throughout its range of sidewise-shifting movement. The slots are slightly largely than the headed studs to also allow some rotational shifting on the studs, of the adjustable “U”-channel with respect to the table to accommodate different angularities (non-parallelisms) of the chair arms with respect to each other.

[0023] Thus the writing table is firmly held against lateral shifting by the fixed “U”-shaped channel having more closely spaced sides and which snugly engage the sides of the chair arm. It is easily mounted because the adjustable channel can be shifted laterally and rotationally. The table is latched against vertical displacement by the inwardly extending portions o the biased pivoted legs of the channels.

[0024] The fixed “U”-shaped channel may be a mirror image of the adjustable “U”-shaped channel, except for the absence of slots accommodating mounting of the flexible channel on the headed studs of a plate fixed to the underside of the writing table. The bite of the other or fixed channel is secured directly to the bottom of the writing table.

[0025] Like the outside leg of the adjustable “U”-shaped channel, the outside, pivoted leg of the other or fixed “U”-shaped channel is biased against the chair arm in the mounted condition of the table and thus frictionally engages it. The friction resulting from the biased engagement the other or fixed “U”-shaped channel with its chair arm, and the friction resulting from the biased engagement of the pivoted leg of the adjustable “U”-shaped channel with its chair arm, together materially restrain endwise movement of the table. The table can be placed in any endwise position desired by the student upon mounting the table on the chair's arm rests.

BRIEF DESCRIPTION OF A PREFERRED INVENTION EMBODIMENT

[0026] These and other objects, features and advantages of the invention will become apparent from a reading of the following specification when considered with the accompanying drawings, wherein:

[0027]FIG. 1 is a view in perspective of a student in the middle seat of a row of three auditorium seats, utilizing a writing table according to the invention;

[0028]FIG. 2 is a view in perspective of the underside of a writing table of FIG. 1 being held above the arm rests of the middle seat of the row of three auditorium seats;

[0029]FIG. 3 is an enlarged view in perspective of a portion of the underside of a writing table shown in FIG. 2;

[0030]FIG. 4 is a sectional view of the adjustable “U”-shaped channel according to the invention, as if taken along the section line 4-4 of FIG. 5; and

[0031]FIG. 5 is a bottom diagrammatic view of a portion of the adjustable “U”-shaped channel sectionalized in FIG. 4 and shown on the left side in FIG. 2 and 3 drawings.

DETAILED DESCRIPTION OF A PREFFERED INVENTION EMBODIMENT

[0032] Referring now particularly to the drawings, there is shown in FIG. 1 a student seated (arbitrarily) in the middle chair generally indicated by the numeral 10 of a row of three conventional auditorium chairs generally indicated by the numeral 12. Each chair includes a seat 14 (FIG. 2) mounted via side supports 16 on the auditorium floor and pivotal upwards thereon to facilitate walking there past when sets of chairs are arranged in rows, and maintenance; adjacent chairs share a common side support. Each chair also includes two arm rests (each in the nature of a generally horizontal board) 18, one on each side of the seat 14 and hence on each side of the seated student's body; the arm rests 18 are fixedly mounted on the respective side supports 16.

[0033] A writing table generally indicated by the numeral 20 is stably mounted in front of the seated student on the arm rests 18 of the chair 10 in which she is seated. The writing table includes a generally rectangular board 22 having a smooth upper surface for writing and spaced rearwardly-extending arms for mounting it on the arm rests 18. The board's underside (FIGS. 2-5) mounts the apparatus for stably, yet easily, securing the table upon the chair arms rests 18. The apparatus includes a laterally- and angularly-floating adjustable “U”-shaped channel generally indicated by the numeral 24 and a fixedly-mounted “U”-shaped channel generally indicated by the numeral 26.

[0034] The laterally- and angularly-adjustable “U”-shaped channel 24 is floatingly mounted downwardly open-faced by its double-layered bite (FIG. 4) generally indicated by the numeral 28 along the left hand edge (as seen in FIG. 2) of the bottom of the board 22. The double-layered bite 28 is formed of an outer layer constituted in effect of abutting lateral extensions of the two legs 37 and 38 of the channel, spot welded to an inner plate 29 of the width of the bite to form a unitary structure. The outer layer is provided with laterally-extending slots 30 somewhat loosely receiving headed studs 32 fixedly (in conventional fashion) depending from a plate 34 secured to the bottom of the board 22 via screws manipulated through corresponding holes 35 in the bite 28. The heads (of greater lateral dimension than the width of the slots 30) of the studs 32, reside in slots 36 in the inner layer 29 of the bite 28. The slots 36 in the inner bite layer 29 are larger than but concentric with the slots 30 in the outer layer, to accommodate movement of the heads of the studs 32 therein while they hold the bite outer layer and hence the channel floatingly in place as it is adjusted with respect to the writing table to fit the particular chair's arm rests. The inner layer slots 36 also provide a recess to shield the student from harmful engagement with the studs 32. It results that the channel 24 may shifted laterally with respect to the board 22, the slots 30 sliding laterally upon the headed studs 32, to enable seating of the adjustable channel 24 upon its arm rest in spite of any non-standard distance from the other. It also results, because of the loose fitting of the headed studs in the slots, that the channel 24 may be rotated horizontally with respect to the board 22, the slots 30 at one or the other end of the channel rotating laterally upon or about a headed stud or studs 32 on the other or one end of the anchor plate 34, to enable seating of the adjustable channel 24 upon its arm rest in spite of any non-standard angular relationship with the other.

[0035] The outside leg 38 of the “U”-shaped channel 24 is secured as by spot welding a lateral flange 41 formed integral with it to one plate 43 of a spring-biased hinge (commercially available plate piano-hinge) of which the other plate 45 is one of the aforementioned lateral extensions forming the outer layer of the bite 28; thus the channel outside leg 38 is arranged for pivotal action at the juncture with the bite 28 (FIG. 4) about the hinge pin 39. The leg 38 is spring biased to a latching position in which it lies along a side of the chair arm rest 18 and an inwardly-extending portion 47 on the free end thereof lies underneath the chair arm rest 18 when the writing table is properly mounted. The leg 38 can be manually moved from that position by engaging the underside of its flange 41 with the fingers of a hand to pivot it about the hinge pin 39.

[0036] When the latching position is not being defined by engagement of the biased leg with the side of the arm rest, it is defined by a down-turned flange 48 formed on one edge of the inner plate 29. The lower end of the flange 48 is engaged by the biased leg 38 at the juncture with its flange 41. The biased leg can be deflected from the latching or home position upon the inwardly-extending portion 47 engaging the chair arm rest 18 as upon chair mounting of the table.

[0037] The inner plate down-tuned flange 48 also helps to securely fix laterally the seated channel 24 with respect to its arm rest, the channel being precisely dimensioned to fit snugly thereon. The channel will be securely fixed (latched) vertically thereon by the engagement of the underside of the arm rest 18 by the inwardly-extending portion 47 on the free end of the biased leg 38.

[0038] The fixedly-mounted rigid “U”-shaped channel 26 is a duplicate of the laterally- and angularly-floating adjustable “U”-shaped channel 24, except for the omission of the slots 30 and 36 in the bite 29 and a different mounting on the writing table. In lieu of the utilization of the headed studs 32 and their anchor plate 34, the channel 26, reversed end-for-end with respect to the adjustable channel 24 to place its latching leg 38 outside, is fixedly secured to the writing table 22 by screws using the bite holes 35. As noted above, the channel 26 is first placed on its arm rest (the writing table being positioned to suit endwise by the student), and then the channel 24 is adjusted as needs be laterally and angularly to be received on its arm rest.

[0039] To use, a student would pick up a writing table and take it to an auditorium seat and seat herself or himself. She or he would then place the fixedly-mounted “U”-shaped channel 26 on its arm rest, preferably moving its biased leg 37 out of the way by applying finger pressure to its flange 41. She or he would then place the adjustable “U”-shaped channel 24 on its arm rest, relying on table pressure to shift the channel laterally and/or angularly to align it with its arm rest or physically adjusting the channel with respect to the table if gross misalignment obtained.

[0040] The writing table is firmly held against shifting laterally by the rigidly-mounted “U”-shaped channel 26, its fixed leg 37 and bite inner plate flange 48 snugly and firmly embracing its chair arm rest. Vertical displacement of the table is prevented by the engagement of the underside of the arm rests 18 by the inwardly-extending portions 47 on the free ends of the channel biased legs 37 and 38. Endwise shifting of table is restrained by the friction resulting from the biased engagement of the biased legs of the “U”-shaped channels with their arm rests, and from the weight engagement of the bites of the channels with the arm rests. Weight obtains not only from the weight of the writing table, but also from that of the student's arms and such of the student's body as the student may choose to rest hereon.

[0041] While there has been shown and described a preferred embodiment of the invention, it will be apparent to those skilled in the art that the principles of the invention may readily be incorporated in other and different embodiments. It is thus desired to be limited only by the scope or spirit of the appended claims. 

What is claimed is:
 1. An auditorium-chair and portable-writing-table combination comprising a chair seat, an arm rest in the nature of a generally horizontal board on each side of the seat, and a portable writing table having a writing surface on its upper side and downwardly-opening U-shaped channels on its underside that are received on the respective arm rests, one of said channels being horizontally displaceable with respect to the board to accommodate variations in the relationship of the arm rests with respect to each other.
 2. An auditorium-chair and portable-writing-table combination according to claim 1, wherein the other channel is secured against horizontal displacement to render the mounted table stable against horizontal displacement.
 3. An auditorium-chair and portable-writing-table combination according to claim 1, wherein the other channel is fixed against lateral displacement to render the mounted table stable against lateral displacement.
 4. An auditorium-chair and portable-writing-table combination according to claim 1, wherein one of said channels is displaceable with respect to the board to accommodate variations in the relationship of the arm rests.
 5. An auditorium-chair and portable-writing-table combination according to claim 1, wherein the one of said channels is also angularly displaceable with respect to the board to accommodate variations in the angular relationship of the arm rests, and the other channel is fixed against lateral displacement to render the mounted table stable against lateral displacement.
 6. An auditorium-chair and portable-writing-table combination according to claim 1, wherein the outer leg of one of the U-shaped channels is hinged to its bite and biased inwards thereabout to grasp the associated arm rest.
 7. An auditorium-chair and portable-writing-table combination according to claim 6, wherein the outer leg of the other of the U-shaped channels is hinged to its bite and biased inwards thereabout to grasp the associated arm rest.
 8. An auditorium-chair and portable-writing-table combination according to claim 6, and the other channel is fixed against lateral displacement to render the mounted table stable against lateral displacement.
 9. A universal stable writing table for an auditorium chair having arm rests, comprising a board having an upper writing surface, and downwardly-opening U-shaped channels on the board's underside that are placeable on the arm rests, one of said channels being laterally displaceable with respect to the board to accommodate variations in the spacing of arm rests.
 10. A universal stable writing table for an auditorium chair having arm rests according to claim 9, wherein the other channel is fixed against lateral displacement to render the mounted table stable against lateral displacement.
 11. A universal stable writing table for an auditorium chair having arm rests according to claim 9, wherein the one of said channels is also angularly displaceable with respect to the board to accommodate variations in the angular relationship of arm rests.
 12. A universal stable writing table for an auditorium chair having arm rests according to claim 11, wherein the other channel is fixed against lateral displacement to render the mounted table stable against lateral displacement.
 13. A universal stable writing table for an auditorium chair having arm rests according to claim 9, wherein the outer leg of the one of said U-shaped channels is hinged to its bite and biased inwards thereabout to engage the side of the associated arm rest.
 14. A universal stable writing table for an auditorium chair having arm rests according to claim 9, wherein the one of said channels is also angularly displaceable with respect to the board to accommodate variations in the parallel relationship of arm rests, and wherein its outer leg is hinged to the bite and biased inwards thereabout to grasp the associated arm rest and clamp the board to it.
 15. A universal stable writing table for an auditorium chair having arm rests according to claim 13, wherein the other channel is fixed against lateral displacement to render the mounted table stable against lateral displacement.
 16. A universal stable writing table for an auditorium chair having arm rests according to claim 9, wherein the bite of the U-shaped channel is formed with laterally extending slots, and headed studs fixedly depend from the board and are received in the slots to floatingly laterally support the channel.
 17. A universal stable writing table for an auditorium chair having arm rests according to claim 16, wherein the headed studs fixedly depending from the board are loosely received in the slots to also floatingly angularly support the channel.
 18. A universal stable writing table for an auditorium chair having arm rests according to claim 13, wherein the outer leg is formed on its free end with an inwardly directed portion for engaging the underside of the arm rest and latching the table to the chair.
 19. An inexpensive attachment mechanism for securing a first part to a longitudinally-extending part, comprising U-shaped channel having bite and leg portions to embrace the longitudinally-extending part, said bite portion having inner and outer layers, one of said leg portions being fixed and a lateral extension thereof forming part of one of the biter layers, the other of said leg portions being hinged at the bite had having a hinge portion forming another part of said one of the bite layers, and a plate constituting the other of the bite layers and fixed to the parts forming said one of the bite layers to define an integral structure.
 20. An inexpensive attachment mechanism for securing a first part to a longitudinally-extending part according to claim 19, wherein transverse slots formed in outer layer of the bite portion for receiving headed studs and accommodating channel movement thereon.
 21. An inexpensive attachment mechanism for securing a first part to a longitudinally-extending part according to claim 19, wherein the hinged leg portion is swingable outwards against a bias, and an extension is fixed to the swingable leg for moving it outwards against the bias.
 22. An inexpensive attachment mechanism for securing a first part to a longitudinally-extending part according to claim 20, wherein the outer leg is formed with an inwardly directed portion for engaging the underside of the non-aligned part and latching the part to it.
 23. An inexpensive attachment mechanism for securing a part to a longitudinally-extending part according to claim 20, wherein the, fixed leg portion has an outward lateral extension serving to guide the channel onto the longitudinally-extending part.
 24. An improved auditorium-chair and portable-writing-table combination according to claim 1, wherein headed studs depend from the bottom of the table, and the horizontally displaceable channel is formed with transverse slots in its bite portion that loosely receive the headed studs secured to the table. 